"Valve today announced the release of its Steam for Linux client. In celebration of the release, over 50 Linux titles are now 50-75% off until Thursday, February 21st at 10 AM PST. The Steam client is now available to download for free from the Ubuntu Software Center. Ubuntu is the most popular distribution of Linux used by millions of people globally and known for its well-designed, easy-to-use customer experience." The beginning of the Steambox. We're on the cusp of a sea change in the gaming world.

While what you say is true it's largely irrelevant. You can make it work on any distro with some effort and people have done so and documented how (in some cases posted scripts). Most non-Ubuntu Linux users won't have a problem following these instructions to a successful conclusion.

That said they do make a number of *very annoying* assumptions, not just about library versions but about other Ubuntuy things (like notifications).

I'll still take a dedicated Ubuntu game box over a dedicated Windows one any day.